To the new details about one of the most lethal avalanches in years. Massive waves of snow taking down five experienced snow boarders and a skier in colorado. One man managed to survive. Clayton sandell has the story. Reporter: This morning, friends and family are struggling to grasp how five experts on the slopes became victims of colorado's deadliest avalanche in years. The snow boarders and one skier IN THEIR 30s. Caught by surprise saturday when an avalanche two football fields wide, four football fields long came rail roading toward them. It traveled at the speed of a freight train. Probably moving at speeds 50, 60 miles an hour. Reporter: Rescuer dale atkins took us back to where he sernged for victims. At that speed, that power, you don't have much time. You literally have seconds to try to get out of the way. Reporter: Amid the chaos, one man miraculously survived. A manager at a colorado snow board company was unhurt but paushlly buried. He was able to get snow off his face but he couldn't get free for some time. Reporter: He gt free, hiked to a road, and fashioned down a car for help. Nature doesn't care about our knowledge and skills. Surviving an avalanche saul luck. One fella is able to walk away there this. It's luck. Reporter: For "good morning america," clayton sandell, abc news, loveland pass, colorado.

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